1st Edition

Polyurethane Casting Primer

By I.R. Clemitson Copyright 2012
    326 Pages 98 B/W Illustrations
    by CRC Press

    326 Pages
    by CRC Press

    Omitting complicated chemistry concepts, Polyurethane Casting Primer presents practical details on the casting of polyurethane products to assist readers in their daily work. It covers fundamental methods, explores hands-on design and production topics, and keeps theory to a minimum.

    The book fully explains casting and allied processes. Starting from a "bucket and paddle mix" open pour, postcuring machining, bonding, and painting, it discusses how to produce quality products continuously. The author describes the necessary precautions for maintaining the health and safety of workers. He covers the properties of polyurethane systems, the tests and results of polyurethanes commonly used in compression, and the correct grade and processing of polyurethanes for meeting customer requirements. He also reveals how to fix issues such as molding problems and premature end of life.

    The versatility of polyurethane enables a wide range of applications, from simple, noncritical parts to vital engineering products. This book guides manufacturers in designing and producing polyurethane products. Batch calculations are available for download at www.crcpress.com

    Introduction
    Polyurethane Family of Plastics
    Castable Polyurethanes
    Comparison to Other Plastics
    Health and Safety

    Fundamentals
    Basics
    Fundamental Ingredients
    System
    Types of Polyurethane Systems
    Commercial Types
    System Selection
    Commercial Types of Polyurethane Systems
    Processing Selection

    Mixing and Casting Polyurethanes
    Basic Mixing and Casting
    Background to Mixing and Casting
    Calculations
    Adjustments to the Amount of Curative Used
    Method
    Curing and Postcuring
    Calculations
    Tables

    Supplementary (Additional) Casting Processes
    Thick Cross-Sections
    Bonding
    Finishing
    Postcure Bonding
    Painting
    Epoxy Blends
    Millable Polyurethanes

    Design Considerations
    Quality of Part Required
    Draft and Undercuts
    Shrinkages
    General Considerations in Mold Design
    Parts in Compression
    Bonded Parts
    Wheels

    Standard Polyurethane Properties
    Introduction
    Basic Comparisons
    Viscosity of Prepolymers
    Pot Life of Prepolymers
    Curing and Postcuring
    Slow Curing
    Effect of Backbone Type
    Polyether Urethanes
    Range of Values within a NCO Level
    Aliphatic Polyurethanes

    Testing Polyurethanes

    Quality Control and Assurance Testing
    Introduction
    Raw Materials Testing
    Finished Products Testing

    Standard Tests for Product Evaluation
    Introduction
    Prepolymer Properties
    Processing Information
    Cured Polyurethane Properties
    Details of Procedures

    Investigations into Structural Properties
    Introduction
    Structure from a Material Science Point of View
    Structure from an Engineering Point of View
    Infrared Spectroscopy
    Nuclear Magnetic Resonance (NMR)
    Differential Scanning Calorimetry (DSC)
    Dynamic Thermal Mechanical Analysis (DTMA)
    Thermal Gravimetric Analysis (TGA)
    Scanning Electron Microscopy (SEM)
    Atomic Force Microscopy (AFM)
    Small-Angle X-Ray Scattering (SAXS)

    Chemical Resistance
    Introduction
    Alphabetical List of Chemicals
    Suitability Listings

    Polyurethanes under Load
    Introduction
    Deformation Relationships
    Stress
    Shear
    Compression Set

    Flops
    Introduction
    Early Detection
    Molding Problems
    Problems on Demolding
    Potential Problems
    Returns from Customer
    Premature End of Life

    Health and Safety
    Isocyanate Vapors
    Curatives
    Catalysts
    General Chemicals
    Material Safety Data Sheets (MSDSs)
    Heat
    Electrical Equipment
    Compressed Gas Lines
    Handling Tools, Materials, and Equipment

    Glossary

    Appendix

    Biography

    I.R. Clemitson worked in the chemical industry for 45 years, primarily involved with the production and development of rubbers and polyurethanes. He is a chartered member of the Royal Australian Chemical Institute (MRACI CChem).

    … a hands-on, practical approach to castable polyurethane compounds … very user-friendly.
    —Michael Szycher, Sterling Biomedical, Lynnfield, Massachusetts, USA